The present invention relates generally to monolithic techniques for micromachined technologies and integrated circuits. More particularly, the present invention provides a method and resulting device including both MEMS and integrated circuits using standard foundry compatible processes. Merely by way of example, the invention can be applied to microphones, motion sensors, rf devices, bio-systems and sensors, energy devices, pressure sensors, motors, electric generators, combinations of these, and the like.
Micromachined inertial sensors have been widely used in automotive and industrial applications for the past decades. Micromachined sensors have many advantages over macro electromechanical sensors. Micromachined devices are fabricated in a similar way as IC chips and have significant reduction in form factor. In addition, micromachined sensors have superior performance, lower power, and lower cost comparing to macro electromechanical sensors.
The incumbent micromachined inertial technologies, however, are based on MEMS fabrication processes such as bulk and surface micromachining techniques, which limit the level of integration of MEMS and CMOS, and are difficult to scale and leverage IC foundries' capability and capacity.
Thus, it is desirable to have an architecture that enables monolithically integration of MEMS on CMOS using IC foundry-compatible processes, which yields the highest performance, smallest form factor, and lowest cost comparing to the incumbent MEMS inertial sensors.